Most inkjet printers have a scanning or reciprocating printhead that is repeatedly scanned or reciprocated across the printing width as the media incrementally advances along the media feed path. This allows a compact and low cost printer arrangement. However, scanning printhead based printing systems are mechanically complex and slow in light of accurate control of the scanning motion and time delays from the incremental stopping and starting of the media with each scan.
Media width printheads resolve this issue by providing a stationary printhead spanning the media. Such media width printers offer high performance but the large array of inkjet nozzles in the media width printheads is difficult to maintain. For example, there is a need to maintain the printheads which becomes exceptionally difficult when the array of nozzles is as long as the media is wide. Further, the maintenance stations typically need to be located offset from the printheads so as not to interfere with media transport.
Some previous systems move the printheads to the servicing stations when not printing. However, when a printhead is returned to its operative position its alignment for correct printing is prone to drift until eventually visible artifacts demand hardware and/or software mechanisms to realign the printhead. In other previous systems, the service stations translate from their offset position to service the printheads while the printheads are raised sufficiently above the media path. Both of these system designs suffer from drawbacks of large printer width dimensions, complicated design and control, and difficulty in maintaining printhead alignment. Further, these systems add size to the printer. Thus, there is a need to have a media wide printhead maintenance solution that is simpler, more compact and more effective for media wide printing systems.
Further, the high media transport speeds used in such media width printers have typically lead to more complex media transport systems in the printers, due to the need to minimize media feed errors. Thus, there is a need to have a media transport solution that is simpler and more reliable for media wide printing systems.